drm/i915/hdcp: Rename hdcp capable functions

Rename hdcp_capable and hdcp_2_2_capable to hdcp_get_capability
and hdcp_2_2_get_capability to properly reflect what these functions
are doing.

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240223081453.1576918-7-suraj.kandpal@intel.com